1. Field of the Invention
The present invention is directed to a method for automatically processing studies acquired by an imaging examination system as well as to a corresponding computerized system for the implementation of such a method.
2. Description of the Prior Art
A number of diseases can be recognized early and treatment measures initiated in time with the assistance of modem imaging examination systems such as, for example, magnetic resonance tomography systems, computer tomography systems, X-ray devices or ultrasound devices. Particularly pathologies such as coronary heart diseases, lung cancer or colon cancer, which are among the most frequent causes of death in the industrialized world, often can already be detected in a very early stage especially with tomographic examination methods such as magnetic resonance tomography or X-ray computed tomography. Regular preventative examinations even of non-symptomatic persons with such methods therefore could certainly considerably improve the chances of curing these diseases. Unfortunately, however, such examinations involve relatively high costs. Among the reasons for these high costs are the very large quantities of image data that arise as well as the time that is required for a finding by a radiologist. Dependent on the type of examination, for example dependent on whether it is a simple examination or a comparative examination with and without administration of contrast agent, one or more measurement series, referred to as studies, are acquired for an examination of a patient. Each of these studios is composed of at least one image, and usually is composed of a number of images from various slices of the examination subject. It can be assumed in a rough estimate that image that, for example, are stored in the DICOM standard (Digital Imaging and Communication) and are composed of an image header, which contains the information about the patient, the exposure location, the exposure time, etc., and include of the gray scale information that represent the actual image, with a data volume of approximately 200 KB. Given the assumption that a total of 1800 images are to be acquired for a complete screening of a patient in a magnetic resonance tomography system given a body height of 1.80 m for the patient and one image per mm, one such examination leads to a data quantity of 360 MB. Dependent on the type of examination, it may be necessary under certain conditions to not only process these images themselves in order to perform a finding for the study; rather, but also the images may have to be compared, for example, to images of preceding studies from other examinations. The quantity of data and the required time are correspondingly increased. One solution for reducing the costs, particularly in screening examinations, would be to make findings in an automated manner. At least the required work time of the radiologist thus can be reduced, since the radiologist would only have to be available only in cases that seem to be critical and/or for a possible spot-check monitoring of the findings. In practice, methods and computer systems already exist for automatically processing studies of imaging examination systems, including a complete evaluation, i.e., for example, a finding of the studies.
One problem of such automatic processing or finding, however, is the high computing capacity required therefor, since computing methods for such radiological applications require a very large number of processor operations, i.e. computing operations, comparison operations or the like, as well as a very large number of data bank queries at different data banks, even on different computers. Particularly in the case of comparison to studies of earlier examinations, extremely large quantities of data must be loaded, for example from an archive server that contains the historical data. The required operations and the transport of the data quantities burden the appertaining computer as well as the network to which the computer and the archive server are connected to a significant extent. Given a number of automatic findings by a computer, in particular, there is the risk that current operation on the appertaining examination system also will be affected and the examination durations therefore will be lengthened. Particularly given examinations wherein a fast finding is necessary, for example given an examination of patients with a suspected cardiac infarction or stroke, this can lead to critical delays. Moreover, longer examination times are relatively uncomfortable for the patient. Finally, longer examination times lead to a lower workload for the relatively expensive examination systems, which again indirectly involves higher costs.